Semiconductor devices incorporated in miniaturized and highly sophisticated electronic devices have become miniaturized, highly densified, and provided with more terminals. The terminals of a semiconductor element include connecting terminals, which are typically connected to a wiring substrate. These terminals have also become miniaturized and densified in accordance with the miniaturization and densification of the semiconductor elements.
One common method for mounting a semiconductor element onto a substrate is flip chip mounting (refer to, for example, Japanese Laid-Open Patent Publication No. 11-186322). The flip chip mounting is implemented by forming protruding electrode terminals (bumps) on a semiconductor element and electrically connecting the bumps, with a conductive material such as solder, directly to pads that are exposed from a protective layer (solder mask layer) on a chip mounting surface of a wiring substrate.
A miniaturized and highly accurate semiconductor element includes bumps arranged with a narrower pitch. This has also narrowed the pitch of corresponding pads. As a result, defects such as solder bridges, which bridge adjacent pads with solder, has a tendency of occurring in such a semiconductor element.